Alex De Minaur has sounded the alarm ahead of his quarter-final match against Jack Draper at the US Open. The two will face each other in the second session match at Arthur Ashe Stadium today (Wednesday).

Before their showdown, 10th-seeded De Minaur practiced for just 15 minutes before leaving the court looking like “the most dejected and lacking energy player.”

Earlier this summer, the Australian had to withdraw from his Wimbledon quarter-final match against Novak Djokovic due to a hip injury. The US Open is the first singles tournament he has played since then.

Before his first Grand Slam quarterfinal, Draper had a successful training session. But when his opponent Arthur Ashe missed a shot before the match, things looked very different.

On Sky Sports, Karthi Gnanasegaram and Annabel Croft revealed that De Minaur left the field after just 15 minutes and they were left standing in front of a deserted pitch. “You might also notice that we have an empty pitch behind us. Alex De Minaur came here at 11am New York time, trained for about 15 minutes and left,” Gnanasegaram said.

And the punches he threw during his 15 minutes on court worried Annabel Croft, who claimed he looked “dejected” as he left. The former British tennis player explained: “There couldn’t have been a greater contrast to Jack Draper’s training session.”

“I don’t think I’ve ever seen a warm-up that short and I’ll be honest with you, we talked about how energetic and aggressive Jack Draper looked.

“I got the impression that De Minaur didn’t really want to move his feet. Either he was trying to conserve energy or he was just feeling very lethargic. He barely hit any groundstrokes from the back of the court, went to the net, hit a few volleys and played each one for about five minutes.”

Croft was particularly concerned by De Minaur’s attempts to work on his serve. She continued: “I’ve never seen players serve after 10 minutes of warming up for such a big match. And then he made some, well, I say, serves that didn’t register on the clock, so they were very sluggish serves.”

“Then he started to step up the pace a little bit, but the only serves he made in deuce were forehands down the middle, which was quite interesting. Then he switched to the attacking side. Again he went down the middle, like he was serving to Jack Draper’s backhand, and then right at the end of the warm-up he served a couple of balls wide out to the forehand.”

The world number 10 ended his session quickly and looked unconvincing as he left. “He tried to hit a couple of winners right off the next serve and then he just gave the thumbs up and it was like practice was over, he picked up his water bottle,” Croft added.

“If you were to judge from practice, he would have definitely won today’s practice game. But after picking up his water bottle, he left the field looking like the most dejected and lacking energy player about to play an important game against Jack Draper. You can interpret that however you want, but it was not a great practice.”

But former British tennis stars Laura Robson and Tim Henman were reluctant to make any hasty assumptions about the 25-year-old’s physical condition. “It was 15 minutes. At the end he hit his serves well, it didn’t look like he was going to follow up with his shoulder, I don’t know,” Henman said in response to talk about his training session.

Robson interjected: “But you wouldn’t really give it your all anyway, would you?” Henman replied: “You would hit harder to get into your rhythm and loosen up.”